Two-Digit Addition & Subtraction — Answer Key
Part A: Multiple Choice
Circle the best answer for each question.
1. What is 48 + 35?
A) 73
B) 83
C) 82
D) 93
Add the ones: 8 + 5 = 13, write 3 and carry 1. Add the tens: 4 + 3 + 1 = 8. So 48 + 35 = 83.
2. Which subtraction problem requires regrouping?
A) 86 - 42
B) 73 - 31
C) 61 - 28
D) 95 - 53
In 61 − 28, the ones digit 1 is smaller than the ones digit 8, so you must regroup 1 ten from the tens place to make 11 ones before subtracting.
3. What is 90 - 46?
A) 54
B) 44
C) 56
D) 34
Regroup 1 ten so 0 ones become 10: 10 − 6 = 4. Then 8 − 4 = 4 in the tens. So 90 − 46 = 44.
4. If you add 57 + 28, what digit goes in the ones place?
A) 5
B) 7
C) 3
D) 15
Add the ones: 7 + 8 = 15. Write 5 in the ones place and carry the 1 ten over to the tens column.
Part B: Fill in the Blank
Write the correct answer on each line.
1. 76 + 18 = 94.
Add the ones: 6 + 8 = 14, write 4 and carry 1. Add the tens: 7 + 1 + 1 = 9. So 76 + 18 = 94.
2. 91 - 54 = 37.
Regroup 1 ten so 1 one becomes 11: 11 − 4 = 7. Then 8 − 5 = 3 in the tens. So 91 − 54 = 37.
3. 43 + 49 = 92.
Add the ones: 3 + 9 = 12, write 2 and carry 1. Add the tens: 4 + 4 + 1 = 9. So 43 + 49 = 92.
4. 85 - 38 = 47.
Regroup 1 ten so 5 ones become 15: 15 − 8 = 7. Then 7 − 3 = 4 in the tens. So 85 − 38 = 47.
5. 66 + 27 = 93.
Add the ones: 6 + 7 = 13, write 3 and carry 1. Add the tens: 6 + 2 + 1 = 9. So 66 + 27 = 93.